The present invention relates to a hinge device for casings and, more particularly, to an improved hinge device for casings of the type comprised of an upper cover and a body portion.
Many hinge devices are used in casings, such as portable computers, of the type having an upper cover and a body portion, to discretionally retain the upper cover in a desired position relative to the body portion by friction. However, such hinge devices tend to malfunction after long-term usage. For example, one type of the hinge devices utilizes a spring around a pivotal axle, and by means of the friction between the tightly-contacted surface of an inner periphery of the spring and an outer periphery of the pivotal axle to achieve the above-mentioned purpose. However, after long-term usage, the spring and the pivotal axle are unable to provide a sufficiently tight contact relationship therebetween due to abrasion.
Therefore, there has been a long and unfulfilled need for an improved hinge device to mitigate and/or obviate the aforementioned problems.